There has already been considerable discussion in the medical literature concerning the problems involved with respect to the willingness, obedience and conscientiousness of the patients to take, in true conformity with the prescribed dosage and at the specified times, the medicines or drugs prescribed to them by the physician in charge.
From the said literature, it is possible to infer essentially the following:
1. There exists a significant minority of patients who make major mistakes in the "self-administration" of the prescribed drugs.
2. These mistakes are made more or less regardless of the seriousness or virulence of the respective disease.
3. Judging by experience, the patients generally so behave as to hide or conceal from their physicians any errors they have made with respect to the dosage or to the taking of drugs; in this connection it can also be stated that, on the basis of the behavior in medical terms and of the diagnostic acumen, most patients are actually successful in being able to conceal from the physicians in charge the nature and extent of the dosage mistakes or errors that they have made.
4. The error which generally occurs most frequently with respect to the drug dosage consists in failing or neglecting to take the prescribed drug.
5. A secondary dosage error which occurs less frequently and with less probability is generally one which consists in forgetting that the specified dose has already been taken, so that it is taken once again after approximately one hour or a longer time interval has elapsed.
Because of these circumstances, it is naturally extremely desirable from the therapeutic viewpoint to search for means and ways which ensure the following:
1. Monitoring of the patient community with respect to its behavior in the taking and dosage of the medicines prescribed to it by the physician.
2. Improvement of the behavior of the patients with respect to the dosage and taking of the drugs.
3. Minimization of the therapeutic consequences due to errors that the patients make in dosage.
4. Minimization of the probability that the physicians in charge will then misinterpret the errors made by the patients with respect to dosage and taking of medicines as:
a) failure of the expected effectiveness of the drug; PA1 b) necessity for prescribing a larger dose than before; PA1 c) necessity for prescribing an additional drug; PA1 d) necessity for prescribing a stronger drug than the first; PA1 e) worsening or deterioration of the condition of the patient, and/or PA1 f) wrong diagnosis of the condition of the patient.
The mistakes and errors made by the patients with respect to the "self-administration" of the drugs prescribed to them can naturally lead to an unnecessary aggravation of the costs, time, suffering and risk to which the patient is exposed in achieving a cure or an alleviation of his illness. Accurate monitoring and checking of the drugs actually being taken would therefore lead to a great improvement as regards the quality of the therapy which is achievable with the available medicines.
According to the prior art, there already exist various means and ways of monitoring "self-administration" by the patients of the drugs intended, e.g., for oral application, but these known means and ways with few exceptions are all to be described as indirect, more precisely inasmuch as they do not provide real evidence that a prescribed medicine has actually been taken in the specified dosage. Moreover, in cases in which various strengths of the dosage are available for the patients, these known measures are not able to reveal in which dosage strength the medicine has been taken by the patient.
The currently available methods and techniques for monitoring of the oral taking of drugs can be divided into two categories: a) the "continuous" category; and b) the "intermittent" category.
In the continuous category, there already exists a number of applications of electrical and mechanical means which are used for the establishment or the initiation of appropriate measures if an oral form of application, e.g., pill, tablet or capsule, has been removed from its associated packaging. In this connection, the following is to be understood by "appropriate measures": the recording of the time, the tripping of an alarm or the transmission of a signal to a monitoring device, disposed, for example, in a remote location, or to a third person occupying a remote location.
However, by none of the methods explained above is it really possible to observe or confirm in which strength or dosage a medicine has been taken, if at all, by the patient.
Furthermore, various measures for observing or ascertaining dosage errors are known in the intermittent category. Such measures consist in, for example, intermittently taking samples of the blood, of the urine or of other body fluids of the patient and of analyzing these samples, in order to directly determine either the drug itself or a metabolite of the drug or very specific chemicals, the presence of which unequivocably proves that the drug in question has been taken by the patient.
By means of such measures and methods, it can be established that the drug in question has actually been taken, and more precisely at some certain time and in some certain dose, although it is not possible therewith exactly to specify "when" the medicine has been taken or "how much" of the medicine has been taken. Thus, these known methods suffer from the disadvantages that they are not suitable for extrapolation of occasional measurements or determinations on a continuous recording of when the preparation or drug has actually been taken.
A further known method for establishing whether a patient has forgotten to take a medicine in the specified dose consists in monitoring the opening and closing of the drug package or the removal of a medicine dose from the package by the patients, for example according to West German Patent 3,335,301 or West German Offenlegungsschrifts 3,530,356 and 3,504,431.
However, it is not even possible by means of these known methods to provide proof that the specified dose has actually been taken by the patient, but therewith it can be established only whether or not the drug package had been opened and not whether the medication was actually taken by a patient.